A multi-output DC-DC converter supplies a current to multiple output destinations in predetermined order by predetermined number of times. The output destination is determined by time sharing control that turns on any one of switches respectively connected to the multiple output destinations at a predetermined period. Moreover, each output can be suspended at optional timing based on a control signal from the outside. However, when one of the outputs is suspended based on the control signal, the current is not supplied to any output destination during the period in which the suspended output would output a current under normal circumstances.
Moreover, when the multi-output DC-DC converter uses one of the outputs as a power source for a control circuit thereof, there is a problem that an entire circuit is suspended when the output power to the control circuit is reduced and the control circuit is suspended. To deal with the problem, there is known a method in which a circuit that suspends all other outputs, when a voltage of output used as a power source for a control circuit falls to a threshold value or less, is added. However, in the time sharing control, the time allocated to each output is not changed, and thereby, waiting time occurs before that power supply to the required output destination is started. Therefore, it takes time to recover the output voltage to the control circuit. In this way, there is a problem of inefficiency that, even though other outputs are suspended, it takes time to start power supply to an output destination to be given priority.